1. Field of the Invention
The present invention relates to a vehicle air bag, and more particularly to a side air bag directional guide system.
2. Background and Summary of the Invention
Side air bags have been previously designed to be mounted in a seat of a vehicle and to be deployed through a seam in a vehicle seat cover when a side impact of the vehicle occurs. An example of such a side air bag system is disclosed in U.S. Pat. No. 5,498,030 issued to Hill et al on Mar. 12, 1996. Hill et al discloses an air bag module including an inflater for generating gas and an air bag coupled to the inflater and deployable upon generation of gas by the inflater. The pouch is made of a fabric material and serves as both the housing and cover of the module. The pouch has wall portions surrounding the air bag and inflater and defining a pouch interior containing the inflater and air bag substantially therein such that the inflater and the air bag are housed within the pouch. The pouch is also provided with a frangible seam being breakable to form a pouch deployment opening. Upon air bag deployment, the air bag breaks open the frangible seam of the pouch to permit deployment of the air bag out through the pouched deployment opening. A problem with the design of the Hill et al disclosure is that the air bag will not always deploy through the seam in the trim cover of the vehicle seat as intended. In particular, due to various factors, such as the elasticity of the trim material, the relative strength of the stitched seam and the compressibility of the surrounding underlying foam, the air bag may on occasion rupture the trim at a point other than at the seam, thereby possibly resulting in the bag being improperly deployed. To address this problem, it has been proposed that the stitched seam in the trim material be weakened. However, this can have the undesired effect of reducing the long term durability of the seat trim and result in premature separation or splitting of the seam.
Accordingly, it is an object of the present invention to provide a side air bag directional guide system which reliably directs a deployed air bag through a seam in the vehicle seat. This, and other objects of the present invention, are obtained by providing an air bag directional guide system in a vehicle seat including a seat back having a seat cover with an air bag mounted inside of the seat cover. A membrane is wrapped around the air bag unit and has first and second ends connected to a seam in the seat cover. In the preferred embodiment, first and second ends of the membrane are stitched into the bolster seam in the trim cover when the seam is sewn.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood however that the detailed description and specific examples, while indicating preferred embodiments of the invention, are intended for purposes of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.